This post was written by Hatchet reporter Drew Lawrence.

Students, city residents and visitors lined up in Lisner Auditorium on Friday night to have books signed by author and financial journalist Michael Lewis, who spoke about his newly released Wall Street read.

The day after “Flash Boys: A Wall Street Revolt” was published last month, the Federal Bureau of Investigation announced that it had been looking into high-frequency traders and insider trading.

Lewis, known for his bestseller “Moneyball: The Art of Winning an Unfair Game” and other non-fiction works, said his new book focuses on Brad Katsuyama, the founder of IEX, who he called a “smart, ordinary Joe.”

Lewis came to dive into the “darker workings of our financial system,” said Bradley Graham, co-owner of Politics & Prose, which organized the event that’s part of its “Newsmaker Series.” Through a partnership with Lisner, the bookstore has also brought John Heileman and Mark Halperin, Elizabeth Smart and Doris Kearns Goodwin to campus to speak.

The book follows Katsuyama’s investigation into high-frequency traders, or Wall Streeters who use complex algorithms to cut stock trading down to fractions of a second.

“Technology has greatly reduced the need for WS,” Lewis said.

He said Wall Street has had to resort to complicated measures of trade so “people on the other side” will not understand what they are buying. These high-frequency trade exchanges like the New York Stock Exchange charge a fraction of a penny to generate high-speed information, allowing them to gain a sneak peek at upcoming trades.

High-frequency traders then use information that’s collected when someone buys or sells stock “to collide with the ordinary investor.”

“It is another way that WS has found to bill people without actually showing them the bill,” he said.

Andrew Sullivan of The Dish moderated the conversation about Wall Street ethics, gender in the business world, high-frequency trade and the “moral impulse” of some of Lewis’s characters.

“Michael’s books are about human character,” Sullivan said to the packed audience, adding that the characters had “cause to live their lives like they wanted to look back on it.”

Lewis called Katsuyama a “warrior,” who gives the public a reason to still trust Wall Street by trying reform the system.

“I get enormous pleasure telling a story that is satisfying to me,” he said, “I get moved by things, and I found what Brad did was moving.”